You must have +12v and -5v hooked up post-onboard-regulator stage otherwise
you only get an inch wide playfield. The video circuits use strange amplifiers
and stuff to stretch and scroll the playfield, they use the less than normal
voltages, nothing else :)

PCB pictures
:

PCB #1 - fully working

PCB #2 - garbage
on bootup - came out of the actual machine, needs fixing.